DTC Diagnosis Procedure
- CHECK DTC PRIORITY
If DTC P0139 or P0159 is detected with DTC P0137, P0138, P0157 or P0158, perform trouble diagnosis for DTC P0137, P0138, P0157 or P0158.
Is applicable DTC detected?
YES
Perform diagnosis of applicable. Refer to DTC Index .
NO
GO TO 2.
- CLEAR THE MIXTURE RATIO SELF-LEARNING VALUE
- Clear the mixture ratio self-learning value. Refer to Work Procedure .
- Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0171, P0172, P0174 or P0175 detected? Is it difficult to start engine?
YES
Perform trouble diagnosis for DTC P0171, P0174 or P0172, P0175. Refer to DTC Description or DTC Description .
NO
GO TO 3.
- CHECK HEATED OXYGEN SENSOR 2 GROUND CIRCUIT FOR OPEN AND SHORT
- Turn ignition switch OFF.
- Disconnect heated oxygen sensor 2 (HO2S2) harness connector.
- Disconnect ECM harness connector.
- Check the continuity between HO2S2 harness connector and ECM harness connector.
DTC
HO2S2
ECM
Continuity
Bank
Connector
Terminal
Connector
Terminal
P0139
1
F57
1
F78
43
Existed
P0159
2
F74
1
- Also check harness for short to ground and short to power.
Is the inspection result normal?
YES
GO TO 4.
NO
Repair open circuit, short to ground or short to power in harness or connectors.
- CHECK HO2S2 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
- Check the continuity between HO2S2 harness connector and ECM harness connector.
DTC
HO2S2
ECM
Continuity
Bank
Connector
Terminal
Connector
Terminal
P0139
1
F57
2
F79
84
Existed
P0159
2
F74
2
77
- Check the continuity between HO2S2 harness connector and ground, or ECM harness connector and ground.
DTC
HO2S2
ECM
Ground
Continuity
Bank
Connector
Terminal
Connector
Terminal
P0139
1
F57
2
F79
84
Ground
Not existed
P0159
2
F74
2
77
- Also check harness for short to power.
Is the inspection result normal?
YES
GO TO 5.
NO
Repair open circuit, short to ground or short to power in harness or connectors.
- Check the continuity between HO2S2 harness connector and ECM harness connector.
- CHECK HEATED OXYGEN SENSOR 2
Refer to Component Inspection (HO2 sensor 2) .
Is the inspection result normal?
YES
INSPECTION END
NO
GO TO 6.
- REPLACE HEATED OXYGEN SENSOR 2
Replace malfunctioning heated oxygen sensor 2. Refer to Exploded View .
CAUTION:- Discard any heated oxygen sensor which has been dropped from a height of more than 0.5 m (19.7 in) onto a hard surface such as a concrete floor; use a new one.
- Before installing new oxygen sensor, clean exhaust system threads using Oxygen Sensor Thread Cleaner [commercial service tool (J-43897-18 or J-43897-12)] and approved anti-seize lubricant (commercial service tool).
INSPECTION END